The Use of Metastable Austenite to Increase the Wear Resistance of Steels of the Pearlite Class

Abstract

The wide application of steel 110G13L for armor plates in mills and crushers makes it urgent to search for alternative materials with close or sufficient operational stability in conditions of shock abrasive wear. A promising path in this direction is the replacement of steel 110G13L with high-carbon pearlitic steels. The aim of this work is a comparative study of the relationship between the structure formed in the heat treatment process of the low-alloyed pearlite steels 70X2GSML and 150HNML and their abrasive wear resistance. Special attention was paid to the possibility of using metastable austenite as a structural component, which increases the abrasive wear resistance of pearlitic steels. It is established that the steel of the pearlite class 70X2GSML, after normalization from 850 °C and tempering at 550 °C, can be used for casting armor plates for ball and rod mills, as well as to cast parts subjected to machining and operating under abrasive conditions without significant impact loads. It is shown that an additional reserve for increasing the abrasive wear resistance of steels of the pearlite class - 70X2GSML and 150XNML - is high-temperature quenching with the formation of a metastable austenite in the structure. The maximum abrasion wear resistance is achieved after the high-temperature quenching of steels (1150 °C) in oil, which forms a martensitic structure with a metastable austenite in the amount of 20-70%, which, with wear, turns into martensite with a high friction hardening ability on the wear surface.